Which toddler LL Bean winter coat?

I am trying to decide between which winter coat to get for my 17 month old. He had the Katahdin Parka last year, but it was really bulky (albeit warm), so I was never able to put him in the carseat with it on. I like the look of Bean's Warm-up Jacket, but I'm not sure it will be warm enough (we live in the NY metro area).

I think he would get more use out of the Warm-up jacket because it's not so bulky, and he can start wearing it earlier in the season, but I don't want him to be cold on those really cold days either. We will probably be walking to the park (about 3/4 mile away) on a daily basis.

Some basic questions I'm trying to answer for myself:

How much use will he really get out of a heavy duty parka?
Will it be uncomfortable being so bulky, now that he is an active toddler and a pretty sweaty one at that?
How safe is it to use these jackets in the carseat at this age? I know it's not safe for infants. The warm-up jacket seems pretty thin, like you'd be able to use it in a carseat.
Should I buy the Warm-up jacket now, and wait until it get's really cold to decide if he needs a warmer jacket? LL Bean is notorious for selling out of kid's clothes early in the season (Heck, they were sold out of their swimsuits last April!), and I would hat to miss out.
Should I just go ahead an buy both of them (much to my DH's chagrin) and hope he gets some where out of both of them.


Any thoughts on these coats? TIA!

Links (new at this, so hope it works:)

Katahdin Parka:
http://www.llbean.com/webapp/wcs/sto...feat=ssdpb3160

Warm-up jacket:
http://www.llbean.com/webapp/wcs/sto...feat=ssdpb3160

Sorry, I'm navigating the world of winter coats for my son, too, but I just wanted to let you know that some Katahdin Parkas are on sale right now for $25, so you might be able to get both:

http://www.llbean.com/webapp/wcs/sto...d=pp&feat=dp32

I just ordered the Lands End Squall, and I just ordered the Katahdin, not realizing the Katahdin is bulkier...so maybe that will be the one to go back. There is also a code for free shipping from LLBean.

HTH!

IMO, you'll drive yourself crazy trying to find one as thin as fleece (which is about all that is safe in any car seat, not just an infant one) but warm enough for a long walk outside in the winter. At that age, my DS wasn't interested in playing in the snow, so as long as we had something warm enough to go for a stroller ride outside (and you can always use blankets there), we were fine.

A fleece jacket, a fleece snowsuit, and a heavier coat (not necessarily a $70 coat either - LL Bean has some great sales right now) are probably all that you will need.