That all depends on how much you play. The EX2 is decent, but you’re going to want an upgrade. Now, I’d say the madcatz SE is great for that, because you can swap the parts for authentic japanese parts with little to no trouble at all. But again, how heavily you play, the stock parts can fail sooner than that. If you want a great starter stick that doesn’t use authentic japanese parts, the WWE all stars SE is actually a great choice. Yes, I know, looks kinda icky, but the joystick uses omron microswitches (the brand used in (autheic japanese) sanwa sticks) and higher quality buttons than the SFIV SE. The SFIV SE has been known to fail with its parts. However, it is nice that the EX2 is 5 times harder to mod than the SE, and as opposed to buying a whole new stick, just buy a new joystick and 8 buttons (Generally, people like Sanwa JLF and OBSF-30 buttons, $50 together)
EX2 has been pretty cheap, though, I will give it that. But you’re going to want to save in the long run for a TE or a Hori V series (That is VX or V3, which represents xbox or PS3 respectively, and SA or SE, which represents full Sanwa or full Seimitsu respectively. TE is full Sanwa) stick if you want authentic parts, especially if you like playing on a joystick. The price reflects the quality.