Yeah a 105 makes sense. It is no more expensive and gives you the option of 6x9 later on. You will need to raise the head higher to gain the same image size tho, so consider the stabilty of your enlarger and anticipated print size first. I have a 50 f 4.5 minolta, 80 F4 rodagon, 105 f 5.6 rodagon, 135 componon-s, 150 rodagon etc as some came with enlargers etc (I did not waste money buying mroe lenses than I require. All I will asy is that all were second hand in varying condition and age. All are superb beyond criticism. I am certain that unless you get a dog, you can buy any of the lenses mentioned by others with confidence; its just a case of waiting for the bargain. Look to spend no more than $60-100 or so. My 105 F5.6 was $80 (50).