Which Meshuggah album should I buy?

I think The Ocean are brilliant. Their last album was one of my favourites from that year (2007 if I recall), but they are a different kettle of fish from Meshuggah. They may not be your thing (and possibly boring for you), but they are definitely not generic.

As for Meshuggah, a poster on the first page mentioned it depends on what you prefer and I would agree.

Destroy, Erase, Improve if you like the thrashier stuff.
Nothing (my preferred of these two) and Chaosphere if you want the more groovier, heavy side.
I and Catch 33 if you want a bit more of a textured mindfuck.
 
Oops i meant to say clean guitar, really have no idea why i typed keyboard, maybe something else on my mind.

I dunno, are alot of the songs similar in construction to bleed? cuz inded i do find it boring, even ifi do play close attention to the picking patterns, they are still just open note picking. No melody or anything.
hmm... maybe this is not the band for me.

Right around 2:30 into "Bleed" comes THE most metal moment of 2008 when immediately after just the tiniest of pauses the entire band (including vocals) lurches into a giant and powerful combined noise. I love this song, and cannot get enough of the power of that moment.
 
3:00... into obZen is kicking my ass over and over again at the moment, when the drums comes back in like a machinegun... awesome! But this albums has so many good moment like that its ridiculous.
I need to give the other albums some time to grow.
 
Modern medal? wtf does that mean.
If you want to hear music that has the same type of grooves but uses more than the low B string, check out The Ocean (my personal favorite) but any of the Post Metal Isis knock off bands will do.
I completely disagree with you. The Ocean have potential, but Meshuggah blow them out of the water in their ability to not only be awesomely technical but also craft memorable songs that really stick in your head ('New Millenium Cyanide Christ', 'Rational Gaze', 'Bleed' etc) The Ocean, on the other hand, are obviously great musicians but haven't got the songs to match yet. They were completely tedious when I saw them supporting Opeth recently too. The Ocean, at present, are just another in a very long line of bands over the last few years who have tried to out-Meshuggah Meshuggah but just haven't the songwriting acumen to do so.
 
I completely disagree with you. The Ocean have potential, but Meshuggah blow them out of the water in their ability to not only be awesomely technical but also craft memorable songs that really stick in your head ('New Millenium Cyanide Christ', 'Rational Gaze', 'Bleed' etc) The Ocean, on the other hand, are obviously great musicians but haven't got the songs to match yet. They were completely tedious when I saw them supporting Opeth recently too. The Ocean, at present, are just another in a very long line of bands over the last few years who have tried to out-Meshuggah Meshuggah but just haven't the songwriting acumen to do so.

The Ocean don't sound much like Meshuggah at all, to my ears, let alone trying to sound like Meshuggah. They sound far more like a sludge band to me, and the second disc of Precambrian is far more into a experiemental, post-metal thing. Come to think, they are far closer to the likes of Neurosis and Mastodon than Meshuggah. I much prefer the songwriting of The Ocean as well, they pull in so many different influences from the various corners of metal as well as symphonic and ambient and experiemental angles. Meshuggah is great, don't get me wrong, but they are far more predictable from a songwriting perspective.
 
The 'I' EP is the best thing they've done, 20 minutes of magic chaos.

'Catch 33', 'Nothing' and 'obZen' also owns a lot. I don't like their old stuff, tho'...