Ok, just a thought that occured to me...

I will leave Thailand for just a few hours, returning same day from KL to enter on another 30 day visa exempt stamp.

I am currently here on my Australian passport, but also have a UK passport i.e dual citizenship.

Are there any advantages or disadvantages, to returning on the same passport, or coming back on the alternative,

they both have the 30 day visa exempt ofcourse.

It probably makes not a jot of difference? as there is no problem with having back to back stamps in the Aussie..

My gut feeling is to just return on the same passport, but interested to know from seasoned folk on this forum if there is any difference.

Cheers.

No advantages or disadvantages really. Whatever you get the 30 day stay in then you will need to show that passport if needed or asked while in Thailand

I concur, no problem, just remember to use the same one for your next departure.