I couldn't resist....I had to buy a FIGMA!
I have been trying my best to not get lured in by purchasing Figmas because I'm a completionist and also because they are quite expensive.
But I decided...I at least want to get the Vocaloid related Figma's and the K-On! So, I purchased a Tsumugi and also a Yui (which I'm waiting to arrive today, I hope).

Also, ordered a K-On! PSP game from Japan which was also expensive!

If anything...I just hope the completionist bug doesn't bite me, like it did with Marvel Legends and other lines...Yikes! Granted, it was easier to buy Marvel Legends back then at $6.99 vs. a Figma which was literally a whole series. But fingers crossed that my completionist behavior doesn't kick in.










I was afraid of getting a K-On! figure because I knew that I had to at least complete the band. That's why I bought the nendoroid puchi set. When you refer to being a completionist, are you talking about completing a set from a series like K-On! or are you talking about all of the figmas (all 100+ of them)?
All Figma's...hehe but fortunately the bug hasn't hit (thank goodness). All I really want are the K-On! Figmas and Vocaloid-related Figmas but sometimes I see the pictures on figures.fm and I think...You know, I think I want the Haruhi figures too and then I see others and I can see the completist wanting everything. But knock on wood...I have been good so far.
I have the same issue you do, I always have to complete the WHOLE SET. It's like pokemon, "Gotta catch 'em all!" Anyways, The haruhi series might be a little difficult unless you use ebay, as they are discontinued. If yo do go on ebay, hoo boy, do they charge allot! My Kyon was the most expensive out of all of them at the time.
I know all too well how you feel... What initially started as me wanting to just buy Haruhi figmas turned into a vast army. Damn you competitive spirit says my wallet. If you want to save money, my advice is to just complete the K-ON band since the vocaloids are somewhat expensive. Good luck either way.
I'm not sure why, but the picture reminds me of the Ultimate Showdown.
I only have the Yui Alter figure and have no intentions of getting the rest. However, I have one heck of a Miku collection and have to resist buying non-standard Mikus and other vocaloids. It depends on which series I'm into and if the quality of each individual figure matches the rest of the collection.
I haven't bought any Figmas yet. I get tempted by them because they are less expensive than other PVC figures. But I've resisted the urge! The K-On PSP game is REALLY fun.. very costly, but if you enjoy it enough, you'll get so many hours of play out of it, it'll be worth it. :)