I have always had machines that use drop in bobbins and have never had problems with them.
Pros and cons of under machine kind? I noticed Bernina has the under machine kind so did not buy one. I ended up with a H. Viking with the drop in.
So I am curious to know your opinions.

although the two machines i use most have dropin bobbins, i prefer the "under machine" type with a bobbin case. with those, i can control the bobbin tension myself.

Hi,

I presently use all Bernina machines except for my little Singer Featherweight. I think their bobbins hold a lot more thread.
My Bernina Embroidery Machine the 650 Deco has a drop in bobbin. I find if I buy the prewound bobbins for it they seem to last forever. There is nothing more irritating than running out of bobbin thread in the middle of an embroidery design. As for adjusting the bobbin tension. I purchased a second bobbincase to use with heavier threads so that I can play with the tension. While I know how to do it I have never actually used that method. You can handwind the bobbin with really heavy threads, decorative or otherwise as well as even ribbon. If you sew on the reverse side of your project the fancy thread or ribbon shows up on the front when it is finished.

I have an older Viking with a vertical bobbin and can't imagine trying to cope with a drop-in. I can change or wind bobbins without moving what I am working on or un-threading the needle, it's easy to get at under the extension table, slips in and out simply, can be changed by feel with no effort at all, and has jammed only once in 19 years of fairly constant use.

Thanks for the info, sounds like under is a good thing.

My 40 year old kenmore is the only machine i've ever used lol, and it's an underneath bobbin, i'm the same as Patrice, like being able to adjust the tension on the bobbin case

I have used both , and have no preference. :D

I grew up using the under type, and I love them. I seem to have more trouble with the drop in. Now,, I have a sewing buddy, and she likes the drop in. I think it is just the matter of getting use to yours.

I have always had a machine with a under type of a bobbin drop. I have never liked the idea of the bobbin on top just do not know why?

Mine is a drop in bobbin and I have the clear view so that as I piece I can see how much bobbin thread is down there. It's very simple to keep clean and maintain, my mother has only had the ones that load from the side with the bobbin case, and I always used to think it looked confusing, years later I'm sure it's no more or less difficult than the drop in bobbin, it just takes getting used to the machine, I suppose.