My Michelle had some trendy looks but the quality of the construction of the clothing is something I probably would advise away from buying with an eye towards the future (at least in my opinion). It was sold by middle range department stores mostly in the juniors dept/young and modern dept and it copied other looks. There was probably differing qualities, but a lot of things just don't hold up to a lot of washings. I remember picking items up on the racks back then when it was all new and remember how paper thin some things where. I had a jacket/skirt set that had been given to me and remember that the jacket was never the same after washed once(and it was washable). Unlike some items like the lower quality of their line things Biba made in the 60s that were meant to be worn to be trendy a few times and then they would be done (but then again, people must be kicking themselves for not keeping those back in the day), My Michelle did not have the cultural significance of doing anything new. it was just some cute things at a price point.
If you start to be able to spot them repetitiously though...it will help train your eye to look for similar looks in lines with better construction. If someone out there thinks I am wrong and that My Michelle will be worth gold someday and I will regret not hording it, then don't listen to me, but at least don't buy the plainest examples, buy the examples that scream early 90s - black and white (esp half the jacket one color/half the other, colorblocked designs, and polkadots with smaller versions of 80s shoulder pads. You can sell them to folks when the 90s come back as retro and save the couture for when its vintage.