1.0 baby sleeping bag (grobag) recommendation for a little Houdini

[birdseed]

Does anyone know of any other brand other than gro bag that has a central zip and a popper or similar to keep it shut (rather than side zip and shoulder poppers)? My 20 month old DS is escaping from the John Lewis versions we had for his brother and the ones borrowed from a friend as he stands up and tenses his chest (+ suitable grunting noise from effort!) and the shoulder poppers pop and out he climbs.
I don't want to buy original grobag ones unless I can help it, both price and amazon reviews that make the 1 tog ones sound pretty insubstantial are putting me off. (1 tog for summer and holidays, 2. 5 for now)
Thank you.

There are several versions of the original gro-bag and various rip-off ones that have a central zip to the front. When they start being able to undo that, you can turn it round and put it on back to front so that the zip is at the back. When they figure that out as well (never quite observed the technique, but it seemed to involve wedging a toe in the gap at the bottom of the zip and wriggling to force the zip slider upwards) you can try securing the toggle of the zip to the fabric with a lock-headed nappy pin.

When they work that out, you really have to throw in the towel, unless you're prepared to stitch them into the grobag every night. At some point you do have to give up the sleeping bag, otherwise you end up with the hair-raising spectacle of a 2yo climbing out of the cot and walking down a slippery wooden staircase while still wearing the grobag. [eeeeek]

Ebay have some good ones for about £15, or you can inbox me and i'll send you the one that DS has grown out of! Ds is 2.6 and still has room in it, but we're biting the bullet and moving to a duvet!

Tk maxx is good for baby sleeping bags