T-mobile Voice Quality

[htcboy]

I have a quick question for all T-mobile users: When you make phone calls while on an EDGE connection, do you notice a slight background hiss and the words occasionally miss and/or skip. I ask this question for a reason because I have an SIMM unlocked Sprint Touch Pro2 (Thanks PPC Geeks for all your good information ). Last night, I bought an pre-paid T-mobile SIMM card to try out their service and noticed a poorer voice quality than Sprint. I've been considering switching to T-mobile so I could get my hands on a HTC HD2. I understand you need a GSM cellular provider and AT&T is not even a consideration (My mom has them and they are horrible in NYC area). Is there any voice quality difference between EDGE and 3G connections or could my phone be the issue?