@andiyar
yup! you pretty much hit the spot...
I'am signed up currently with SMJ and Rinkya so i get to pick and chose which service i like depending on the auction.
I do have to say though, Rinkya has the best interface among all the deputy services out there. Its very clean, easy to understand and very powerful. For example, in other services, you basically have to know the basic kanji or hiragana for the item you are looking for, and key it into yahoo.co.jp/r/ac
and then you gotta navigate the japanese auction pages to find what you are looking for. i think lucky for us, most of us can do this and know a little or a lot of japanese. But even still Rinkya, has their OWN search engine, which i believe is very good.
for exmaple you can type in "Shakugan no Shana" the ENGLISH name for that anime series and Rinkya's search engine will know that you are looking for 灼眼のシャナ. Its like they have presets for all the popular items or something..
oh well,.....someone get that potato plushie! its out and no one is bidding!
there is a pretty extensive deputy service thread i start @ hongfire talking about all the different deputy services, if you are interested check it out:
http://www.hongfire.com/forum/showthread.php?t=42885