We have one of each type.
The Celsius one runs about 220° or so during hover, or right at set-down. Maybe 205-210° at cruise At 2000 rpm cools down to 180° within a minute and then at idle its down to 150° or so within another minute or less (2 minutes max time). My first one also was usually 210-220 max at cruise, and only slightly higher depending on how far the mixture was leaned. Here's a shot in cruise, during the summer, mixture leaned.

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The other is about 375° max (hot day), but usually closer to 340-350 or so, depending on outside temps. I have seen it at 325° during cruise. During cool down it will stabalize around 310-320 within the 2 minutes. I don't think I've ever seen it get to 380°. Here's a shot of this one on final approach to land earlier this year.

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