Inflatables have their pros and cons. I have seen an auto-inflate operate when only a small corner of the jacket was submerged. This was one we had on our fireboat while working on getting a sinking boat secured to us. To me it inflated to soon. One advantage to them is that you don't feel hindered in movement while wearing one. They are a lot more comfortable. But like you mentioned, you need to keep a re-arming kit with you in case it is used. Also, make sure to read the tag on your unit. If it says it has to be worn to counted as a lifejacket then you better have it on ALL the time. Do not leave it lying in your seat. Even if you are using the trolling motor. You will be cited. If you have a vest type lying out though then you can take the inflatable off with no worry. If the tag does not state it has to be worn then there is no issue.
An advantage to the vest type is that you have one more barrier to cold wind when running down the lake.
Try looking back several pages or type "inflatables" into the search box above to locate the thread we had on this a few months ago.