Recommend me a new shopping cart?

Hello to all the experts here!

I have been using Yahoo MS for many years. While it served the need, it is lacking a lot of functions we need. I understand carts like Magento can probably do all the things I want but I think it might be an overkill since I only sell 6 SKUs (but with color/size options). I was hoping if someone suggest some solutions (hosted or not) with all or most of the below features:

Wholesale customer pricing
Option and Volume Pricing
Out of Stock Msg per at product option level
Inventory Tracking at product option level
RMA system - Automated
Pre-order & Backorder
One time Coupons
Product Reviews system add-on

Thank you in advance. I appreciate any feedback!

Foxycart is easy and very good.