Are you S-Off? If not, you are using the stock hboot. In fact, if you don't know then you are using stock.
What this is about: some of us use modified hboots (or other methods) to change the internal memory partitions. Generally this means shrinking the system space, where the ROM lives, to allow more data space, where user apps and app data live. CM7 hboot is a common example of this, designed to fit the original CM7 ROMs (current CM7 is bigger, and no longer fits the original CM7 table).
That's fine if your ROM is small enough to fit the smaller system space. But NO Sense ROM is that small. So when you see a "CM7" version of a Sense ROM this means that part of the ROM has been moved to the sd-ext partition. This means you can have more "internal memory", but need a bigger ext partition on the card.
If you have the stock setup there is no advantage at all in using the CM7 version. At best you will have less a2sd space for no gain, at worst you may have a lot less free space, or it may not work at all, depending on the size of your ext partition and what other differences there are (i.e. if the CM7 version leaves stuff in internal memory that the stock one would move, because it assumes you have a bigger data partition).