Yikes I wouldn't touch 4X DVD-Rs if you do a lot of burning. They are pretty expensive man.
Right now I use Princo 1x. White tops and purple bottoms for PS2 and Xbox and they work just too sweet.
Good thing a firmware hack just came out for my burner so now I can burn my 1x DVD-Rs at 2x which makes a difference
On the other hand Princos 4X are still at a descent price. Riteks 1x seem expensive not to mention 4X.