In theory, you lose nothing but time by querying an agency you think is too inexperienced to sell your book. But the only reason I can think of for doing it is 1) "just in case nobody else wants it" or 2) "If they offer, I can tell other agents I have an offer, and surely I'll get a better one."
1) It is really hard to say "no" when you have a single offer, even if the agency isn't right for you. Take it from me. I queried an agent who was excellent for certain genres, but after he requested from me, I began to feel iffy about his ability to work with my genre. His offer did not fill me with confidence, but in the end he was my only offer. I had an R&R from another agent, but couldn't say no to the "sure thing." Several months later, we parted ways. It was not a good match, and I knew that going in, but still said "yes." So my advice is always that if you have any misgivings about an agent, you should go with your gut and not bother querying them at all.
2) Hoping that an offer from them will get you an offer from others is a dangerous game. First of all, if an agent isn't interested enough to offer, they're not going to be persuaded by another agent offering. It may take you more time to get through the reading queue without an e-mail about an offer, but their answer will be their answer either way. Furthermore, you may lose out on a potential offer by a busy agent who doesn't think they'll get through your novel by your deadline, and they may reluctantly reject. Now, let's say that you e-mail any agent with a full or partial and maybe a few with just queries too. All reject for whatever reason. You fight that instinct to say "yes" to the offer on the table, and reject them. Now you have to keep querying. But you can't query those agents who already said no, and other agents at those agencies are probably out too because what if one says, "OMG, I just got this interesting query about X," and the agent who just heard you had an offer in hand says, "Wait, did that author lie?" Now you're narrowing your field down for an agency you never wanted to be represented by anyway. Even with the legit reason that I tried the agent who offered and then parted ways, I felt really awkward querying those agents again for the next book.
Anyway, why put yourself in this position? Why be the bad guy who says, "Sorry, I queried your agency, but I'm actually not interested in you"?