Its pretty much 6 of 1 half a dozen the other. As you'll be early enough (assuming travelling on the morning) personally Id go the A5 up to Brickhill and turn into Woburn that way as you wont have any problems at Dunstable as you wont be able to go any faster on the M1 as its 50mph limit. If you prefer motorways then its simple enough to head up the M1 to 13 and come in from there.
If the M1 is moving well I would stay on it to junction 13. Made the big mistake of coming back on the A5 after playing at Woburn a few months back, and it was a nightmare. M1 wasn't bad, but the M25 was the usual carpark. Must admit the drive has put me off playing there again, but hopefully you will all be a lot luckier.
will be a 5.30 am rise for me, jeez its gonna be a long day, warm temps in the afternoon, walking 36 holes, might need friday off to rest my weary bones