IMO 22"s are too big on an E53.

I actually really like the type 132's, so i'd have to say no it's not worth the cost just to upgrade ~but~ if you keep them as a dedicated winter set then it's a good idea.

Keep in mind however that with type 168's(and 87's!) are limited to available tires. AFAIK there are really only three sets that fit (Toyo Proxies, Yoko Advans, and Michelin Diamaris/Latitudes) and they can be pretty pricey.