Hydraulic roller questions

I am currently running a hydraulic flat tappet camshaft, specs are:
274/280ADV, 230/236@.050, .487/.490 lift

Setup is as follows:
Vortec headed 350, 10:1, mild head work, single plane intake, 750CFM carb, 1 5/8" headers

I wanted to go to a small solid roller camshaft, but I am looking at a lot of $$$ to make that happen. What do you guys think of hydraulic roller setups? My biggest concern is that it isnt going to RPM like my current hydraulic flat tappet. I have heard hydraulic roller setups have a tendancy to run into valve float in the upper rpms. I would be shifting this motor around 6500 rpm. Can I make a hr setup work without spending a ton of money on a rev kit? Will an oem style hr lifter support this kind of rpm? Is an oem style lifter more likely to cause valve float than say a Comp XE hr lifter?

Thanks guys!

correct geometry, spring pressure and rev kits can do a lot. I revved to ~7k with no valve float. regularly. 7500 hurt stuff...

I've never seen a Rev Kit that was pricey really. Can you run a 1.46" spring on that head without machine work? Studs pressed in or threaded? I know what you mean about converting to safely run a SR cam and if the same amount of work is required for your heads to do a HR, then I'd suggest just doing a whole new top end. I am doing the same sadly.