Assuming that AMD would price the 5300G at $150, it would retail for 60% less than $359 5700G and 40% less than the $259 5600G. However, according to our testing, the Ryzen 3 5300G delivers 86% of the gaming performance of the 5700G and 90% of the 5600G at 1280x720. That's a great value if we focus specifically on integrated graphics performance, which is really the only reason to consider buying this chip. However, it's clear that this could siphon away AMD's sales of pricier alternatives.
Expecting a $150 price point is probably being a bit too optimistic. AMD's limited 7nm manufacturing capacity means they aren't too interested in selling competitive budget offerings right now, which can be seen with the 5600G's pricing. The 5600G's integrated graphics might be notably better than those included with Intel's 6-core, 12-thread processors, but on the CPU side of things, it's not really any faster than an i5-10400 or 11400. And while it's priced at $260, those competing processors can be had for around $180, meaning you are effectively paying an extra $80 for that better IGP.
And for roughly the same price as a 5600G, you can now get an 8-core, 16-thread i7-10700K, which also falls behind on integrated graphics, but is a decent amount ahead in terms of CPU performance. Those extra cores may not be as much of a concern when comparing an 8-core processor against a 6-core, as both will likely remain relevant for gaming for a number of years when paired with a capable graphics card, but it does become more of a concern with this quad-core part. Just as the 5600G is priced similar to competing 8-core, 16-thread parts, it wouldn't be unexpected for the 5300G to be priced more like 6-core, 12-thread parts. And with some demanding games already choking a bit on 4-core, 8-thread processors, it doesn't exactly seem like the best choice for the long-term. The integrated graphics might be a fair amount better now, but they're still not something anyone interested in gaming performance will want to stick with once GPU prices return to normal.
Overall, it feels like AMD tacked on at least a good 20% over "expected" pricing across the entire Ryzen 5000 lineup, and it wouldn't be surprising to see them do the same for this part as well. Though perhaps they are waiting until it makes more sense for them to release it at retail for a somewhat more moderate price. Ryzen 5000 processors are already seeing price cuts and increased availability as Intel's Alder Lake release looms, and I would expect additional price cuts to come. Still, if they felt they could launch the 5700G for $360 and the 5600G for $260, the 5300G could easily be $160, if not more. There's also the possibility that it could be another 3300X, released to retail at a fairly competitive price, but with only extremely limited supply that made it more or less unobtainable post-launch. The CPU probably shouldn't be reviewed as if it were a great value, when the pricing and availability are only being guessed upon.