The heavy weight Gutermann thread is too heavy for home machines. The light weight is not strong enough for BP applications, as evidenced by Jerry Adams' experience with it, even though he likes it. Among lighter weights, the all poly Mettler Metrosene is not too bad, and there is a cotton wrap poly called Signature that is very strong, but don't know how durable it will be in the outdoors. Have not been able to find the Amann Rasant thread that Roger recommends in a variety of color choices here in the US, although it is in the Australian shops. Spent a lot of time with their Boulder CO branch, and got nowhere. When I find something good that is readily sourced for home users, will post it.
Although the cotton wraps are being discontinued by many manufacturers, the sturdier ones seem to work better in home machines than the all poly. This may be due to greater heat resistance, as Roger suggests, or because the cotton outer wraps just feed better than polyester and nylon. With silnylon, I think the trick is to find just the right thread tension that will allow the fabric to stretch, but will not be too loose when the fabric contracts.