Limit orders are the ONLY type I've ever placed on ETrade (with OTC stocks), though I believe they also mandated limit orders with pink sheet stocks long ago. It's best practice anyhow when dealing with most OTC stocks because they are usually cheap, have many more shares outstanding, and are therefore extremely volatile.

You could get forked very easily placing "Market" orders on the OTC exchange with such stocks (most OTC stocks) and especially if flippers (including MM's) are heavily shorting them after dumping for profit and placing fake "bait and switch" orders to lure in their victims. MM's are like "the house" at the casino. They have the edge and you don't. They can give preference to whatever orders they choose. They break SEC rules regularly and get no more than a slap on the hand for it, which is why the SEC used the "blanket" style of protection to help stop people from getting burned.

Stocks that trade in a more stable manner are usually on a major exchange, are more expensive, and have a much smaller float. There just aren't that many shares out there and manipulation is much more difficult so they are typically much less volatile unless moved by major press releases/earnings reports.