Money vs Horsepower
Hyd rollers can EASILY turn 7K with proper valve train components. I've blasted the stock rollers that high with no float. I know MANY people that have underestimated the power a hyd roller can put out from very mild duration grinds, including a bunch on this board! I know of one 360 that sounds more mellow than a XE268H cammed 360 and puts out 100+ more HP. Sounds like granny should be driving it.
Nice to know that an auto trans is the limiter on rpm, never knew that... please note sarcasm... Guess the guys running cup engines in the 9500+ range better pull those 904's.
Want to run hyd rollers, run them. Want to go solid rollers, go with it. Want to run a solid flat tappet, have at it. ALL can be built to make good power. I know when I have a hyd roller block, that's my first choice in cam selection because of ease of use.
Metalidart, those two cams you posted won't run close to each other at idle with a +15 at .050 duration on the solid flat. They might make the same power up top, but, the idle will be much more mellow on the roller.
Pick your parts, pay your money.