I have a G3 and a Threshold, and briefly owned an E1 that my brother in law now owns. The G3 helped me get over my bias towards electros, and the Threshy is just downright pretty. The E1 that passed through my hands, is still running the stock reg and is the most consistent reg I've seen. Makes me kinda sorry I passed it along, lol. And yes, maintenance is a breeze.
After rereading, and realizing I didn't really answer your specific question, which always annoys me when other people do it, maybe my answer should be, consider a gently used G3, as well as considering the G4. I will say, that some of the issues people had with the DP G series were reg issues that were partly user problems. The regs have since been upgraded to be more user proof. Also, my markers have been decent on air, but understand that the unbalanced spools are not as efficient as some other marker platforms, but they are hardly Tippys either. My Threshy has been good so far, but my Techt bolted G3 is a very smooth shooter. Yes, there are some good aftermarket options. Again, I've seen some nice used Upgraded G3 for reasonable, that's how I bought mine. So, I apologize for not exactly addressing the G4 question, but as was pointed out, the G3/G3 Spec R/G4 platform is largely similar.
Hope that helps,
"Hey, hey, hey...hey now. Don't be mean; we don't have to be mean, cuz, remember, no matter where you go...there you are." - Dr. Buckaroo Banzai Feedback
Last edited by Zero Anon; 08-23-2011 at 11:29 PM.