Choosing a Mig Welder..

From those who may have experience in using or owning both models - which would or do you prefer the I-Mig 230 or the I-Mig275P?
I'm not trying to get feedback on the power of each - but mainly the quality of each build - the smoothness of the arc they lay down - and the expected life of each when it comes to moderate usage.
I realize the 230 is underpowered compared to the 275 but is one over the other considered better relative to their output when it comes to being more 'industrial' or robust.
They both have decent duty cycles and both I'm sure are decent but do (aside from the pulse capability) they equally do good and capable work at their upper end of the power ranges they are spec'd for or is one over the other more capable in that regard?
I would like to replace a very old and large Century Powermate (think Lincoln) welder (225amp 60% duty cycle) ~ 300 lbs - with something a lot smaller and a lot more portable and versitile.
I'm just thinking that the 120/230 volt 230 with its dual voltage capability while convenient, might probably make it more susceptible to issues due to the complexity of having been designed to deal with two possible input voltages.
My old Century/Lincoln lays down very nice beads - can and do Inverter welders match the old and big stuff when it comes to smoothness and does one or the other of these models have an edge in that regard?
I would eventually like to get into aluminum and the pulse is appealing in that sense - is a single pulse machine worthy of consideration as a cheaper alternative to double pulse ones and does either the 230 or the 275 have an advantage in working with Aluminum aside from the pulse capability?
And finally do either have 'coated' circuit boards to help them last in dirtier or poor conditions?
Any general feedback from those who may have experience with both to compare would be much appreciated!
Thanks Very Much - Randy