I'd probably go with a 49 if the standover is bad enough that you feel like you need to return it. The standover height on the 52 is less than an inch lower, but it looks like the 49 has more slope in the top tube so you get a lot more standover without the bike being much shorter from seat to bars. The seat-to-bars dimension (effective top tube length), oddly, seems to be very nearly the same on the 49 as it is on the 52. The only risk real in going with the smaller size is that the seat post might be too short, but it's relatively cheap to get a longer seat post. You could use the Hounder you have now to figure out whether or not that will be a problem by adjusting the seat to a comfortable height, putting tape on the spot when the seat post meets the frame then removing it and making sure you have at least 5 cm between the tape and the minimum insertion mark on the seat post.

FWIW, you should have the saddle high enough that you have just a slight bend in your knee at the bottom of the pedal stroke.