Depends what you're trying to do. If you're trying to play a Gadd lick, you'd probably need to be able to do those paradiddles at about 240+. Gadd plays a lot of his 32nd-note licks at 120 to 124. If you're just trying to work on dexterity and don't care about stealing Gadd's stuff, you're doing fine.
In my book, if you're doing 16th note paradiddles at 150 bpm that's pretty good, though 200 would be better. As far as Gadd goes, do the math and 4 x 240 = 960 beats per minute, which is faster than I can do a single stroke, a pretty high expectation for a paradiddle.
Bottom line is you should be able to match paradiddle speed to your single stroke so you can shift the stroking smoothly between the two as you play rolls. Same with your double stroke and other rudiments ... you want to be able to freely combine them (at will) in different ways to create the sounds in your head. Eventually you won't really know what your hands are doing, they'll just be doing it.