I think a roller cam/lifters are a bit pricey for an average street build. Neat to say you have it, but I feel really not needed. And what if you don't like the cam? Expensive guess.
Flat tappet cams are great for the street, but you will read all the fears about a cam lobe going flat, the cam being soft, or poor quality. Get a cam/lifters from a reputable manufacturer. If they were all that bad, it would not take long for "that" company to get a black eye and be out of business. Sometimes I doubt these claims per say, because there are many dealers/sellers who want you to buy their cam brand - so they blog about xxx cam that went bad and they would never buy another and once they bought xxx cam, they had no problems. Bad press is a great marketing tool. And with a flat tappet cam, you must use an oil with zinc in it or use a zinc additive to prevent cam /lifter wear. Roller cams are not as sensitive -so this is a positive for rollers.
Hydraulic cams are the best for no hassle adjustment -install cam/lifters, correctly lash them, and your done. Solid cams require a periodic check/adjustment of the valve lash. Us hardcore motorheads don't mind the periodic adjustments because they have a unique "clatter" sound that implies "race car." I selected a solid for my build. The solid also gives you a more aggressive cam for the same hydraulic grind. The ramps on the cam are ground differently to open the valve up faster. Slamming the valve open and closed? Isn't that what a cam does? I personally don't feel this is a problem unless you get into some big spring pressures, but then you would not be really using this for a street car, and then you would go roller.
Once you know your actual compression, then you can look around for a cam grind -there are 100 different ones. The things to consider are indeed your compression. Then the RPM range you want to spin the engine and where you want your power band to be. Next is your rear gear ratio, transmission/torque converter stall, and even the weight of the car.
Pontiac knew what to do when they built their engines. They did not build them for high revs. They were built for broad torque and provided a good vacuum to run power brakes. The RPM range was aimed at daily drivers.
You do not have to do a lot of modifications to get a great running street car & still get reasonable gas mileage. I personally don't think the XE cams on a 110 LSA are good for 9 to 1 and up compressions, although no doubt they are used. I feel they are best suited for under 9 to 1 as they build a higher dynamic compression to work with the under 9 to 1 compressions. Use this on 9 and over and you may have an engine that pings/spark knocks unless you use top grade gas or an additive. These cams seem to have a narrower power band, and drop off on power like a stone at whatever peak RPM they are intended for. But they do pull like a freight train with lower compressions.
The cam you see advertised needing higher compression, higher stall converters/4-speeds, 3.55 gears or better are those typically having 114 LSA or more. Why? Because they have more intake/exhaust opening/closing overlap and bleed off some of that higher compression at lower RPM's, but gain it right back at the mid to upper RPM's. You would not want to bleed off any compression on an engine with 9 to 1 or lower. These cams can also be a little "sluggish" on the bottom end so on the street, you might not be too impressed with the lack of get-up-and-go at lower RPM's. Mid-range and up they would however rip your head off -thus you need the slightly higher stall converter and taller gearing to get your engine up the usable RPM range of the cam. This is basically what Pontiac used on the GTO's. These also give a broader torque/HP range and good vacuum.
So, my opinion, the 112LSA cam is just right for 9 to 1 compression if you go aftermarket.(I went with a Crower with the 112LSA) Then you want to select a cam duration number to match your RPM range. Very easy to get caught up in "bragging rights" and over cam on these numbers. Duration wise, probably 260-270 intake, 270-280 exhaust for street manners. Factory Pontiac lift on the valves were .406" with several grinds getting only .374" on the intake and .406" on the exhaust. Pontiac heads flow good at lower lifts, so I would not get too crazy for the street and put it somewhere around .450" max. Now here you could play around with lift. A .406" lift uses 1.5 rockers. Install a 1.65 rocker and you now get .446" lift. The 1.65's will also open the valve quicker which will act like a few more degrees of duration. If the engine responds to the 1.65's then keep them. If it doesn't seem as good, go back to the 1.5's - not all engines will respond favorably to more lift. The use of 1.65's sometimes require a little grinding on the head where the pushrod goes through -you open it up a little so the pushrod does not hit the head. It should not be a problem for under .500" lift, but while at the machinist, I'd have it done just to be safe.
The 1965 factory cam was the 066. 273 In duration, 282 Ex duration, .406" lift, 55 degrees of cam overlap. The 067 cam was 273 In/289 Ex, .406" lift, 54 degrees overlap. The 068 cam was 288 In/302 Ex, .406" lift, 63 degrees overlap. Lift stays the same, exhaust gets more duration to compensate for the restricted exhaust flow. With these 3 factory cams, I think the 068 cam would be the biggest factory cam I would go with, but gas mileage will be down. It may be too much for the 9.0 compression and be a dog at lower RPM's. I like the 067 cam as a better choice & it is going to be smoother with its lowered overlap -should get good gas mileage too. (Had a '67 GTO with this cam: lots of power & upwards of 20 MPG @ 55MPH back then with 4sp & 3.08's) And of course the 066 is good as well.
Invest your money in a good 3 angle valve job & a good dual exhaust system. -this is where you will get big improvements with a Pontiac engine.
There is no "one fits all" cam. Sometimes it is trial and error. There are "safe" cams and others that may not quite work as intended. Many of the cam grinders and/or Pontiac engine builders have a cam data sheet you can fill out with your car's info and they will recommend a cam for you. They know what they are doing. You can also ask them a question on a cam you think would work and they will let you know as well.
That's my opinion ('cause I'm no expert) and I'm sticking to it.
I think geeteeohguy
has the 068 in his lowered compression GTO, so maybe he has some input here as well.