yes, just make them non-exclusive of each other, each in "Edit Plan", first tab.

orangeapple wrote: I may not have explained myself properly.

I meant so that the customer can select just one product, eg it might be listed something like:

Superwidget (including annual subscription) $X

..and they actually end up with two items behind the scenes, the product (Superwidget) and the subscription. The price of $X is the combined value of the subscription and the product.

No worries: one more trial of reply with a suggestion:

1) Make the merchandise plan child of the user subscription plan,
2) make the merchandise exclusive/mandatory + default, and
3) configure user subscription plan to hide children plans when not selected

You need with the above one merchandise plan with each subscription plan.

(or you can integrate all features/integration of the merchandise plan into the subscription instead of the above)