Re: After being at current job for 2 months, previous job calls ....
I would agree. If you liked your old job and only left because you got a better opportunity, then I would go back to the previous employer. They are offering you a better job at a place you liked.
Also, not sure if longevity matters at your old employee in terms of any retirement or benefits that they have but if you come back now, you will probably keep your continuous years of employment.